Home appliance with undistorted front panel curvature

ABSTRACT

A home appliance including an appliance body having an internal framework; a metal panel covering a portion of the internal framework, the panel having a curved portion turned through the curve inwardly toward an interior of the appliance, wherein the panel surface adjacent the curve is substantially smooth and substantially undistorted, the panel being fabricated by engaging a metal sheet with a bender assembly, holding the metal sheet against translational movement, and applying pressure to the metal sheet using a punch having a curved head and being operatively associated with the bender assembly, the pressure being applied by moving the punch against the metal sheet using a damped punch driver operatively associated with the bender assembly.

BACKGROUND OF THE INVENTION

The present invention relates broadly to home appliances having skeletal frames covered with body panels fabricated from metal sheets and, more particularly, to a home appliance, especially a range, having a front panel fabricated from a metal sheet that includes in-turned portions, corners, or both that are smooth and undistorted.

Home appliances, such as ranges, having ovens, steamers, accessory compartments or other openings in the front for user access often include metal panels that extend intermediate the openings to provide a clean, finished look and to cover the essentially skeletal framework that is internal to the range. With such cavities, front panels often include openings themselves to conform to the openings in the framework.

In order to provide ease of cleaning as well as safety and a finished appearance, such openings include radiused or curved corners rather than a stark 90° angle which can result in surfaces that are difficult to reach during cleaning and are not as visually complimentary to the range. Further, the internal structures themselves are typically formed with rounded corners so that the front panel matches the underlying structure. Such corners often include an in-turned portion of the sheet that extends inwardly for a predetermined distance as a flange to accommodate any spaces that may occur between, for example, an oven cavity and the front of the range.

When fabricating front panels, corners are difficult to form without some metal distortion, such as buckling or wrinkling. Small holes may be formed in the front panels at the inward curvature to ease stress on the metal during corner fabrication, however, use of such holes has not solved the problem of unsightly front panels due to metal bending that has resulted in metal distortions around the corners.

There currently, therefore, exists a need for a home appliance with a front panel that includes openings with corners that are smooth and undistorted and a fabrication process and apparatus that will result in such an undistorted and visually appealing front panel.

SUMMARY OF THE INVENTION

It is accordingly an intent of the present invention to provide a home appliance with a front panel including corners that are smooth and undistorted.

It is accordingly an intent of the present invention to provide a home appliance with a front panel fabricated by holding the panel fast against a damped press assembly that provides a gradual pressing action resulting in corners that are substantially smooth and substantially undistorted.

To those ends, the present invention is directed to a home appliance including an appliance body having an internal framework; a metal panel covering a portion of the internal framework, the panel having a curved portion turned inwardly toward an interior of the appliance. The panel surface is substantially smooth and substantially undistorted, with the panel being fabricated by engaging a metal sheet with a bender assembly, holding the metal sheet against translational movement and applying pressure to the metal sheet using a punch having a curved head and being operatively associated with the bender assembly, the pressure being applied by moving the punch against the metal sheet using a damped punch driver operatively associated with the bender assembly.

Preferably the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member having a working surface and defining a receiving cavity adjacent the working surface.

Preferentially, the step of holding the metal sheet against translational movement includes holding the metal sheet using a bender assembly having a plate that engages and applies pressure to the metal sheet prior to the arrival of the punch, and holds the metal sheet stationary during punch application.

It is preferred that the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate supporting the punch in a downwardly directed manner for selective engagement with the metal sheet.

It is further preferred that the step of moving the punch using a damped punch driver includes moving the punch using a punch driver damped with a plurality of springs operatively associated with the bender assembly. Preferably, the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs extending intermediate a spring support plate and a punch plate supporting the curved punch in a downwardly directed manner for selective engagement with the metal sheet.

It is preferred that the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate in a predetermined pattern for balanced force application. Further, the step of moving the punch may include moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate with each of the plurality of springs having a spring stabilizer operatively associated therewith to keep each of the plurality of springs in place intermediate the spring support plate and the punch plate.

Preferably, the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member mounted to a base plate, having a working surface and defining a receiving cavity adjacent the working surface. It is preferred that the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate fixed to the bender assembly in alignment with the base plate to support the punch in a downwardly directed manner toward the receiving cup for selective engagement with the metal sheet at the work surface and receiving cavity. It is further preferred that the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs mounted to a spring support plate fixed to the bender assembly in alignment with the base plate, the spring support plate having a hole defined therein in alignment with the punch for passage of the punch therethrough in a downwardly directed manner for selective engagement with the metal sheet at the work surface and receiving cavity.

It is preferred that the step of applying pressure includes applying pressure to the bender assembly in a machine press.

The present invention is also directed to a range including a range body having an internal framework and a metal panel covering a portion of the internal framework, the panel having a curved portion turned inwardly toward an interior of the range, wherein the panel surface is substantially smooth and substantially undistorted. The panel is fabricated by engaging a metal sheet with a bender assembly, holding the metal sheet against translational movement and applying pressure to the metal sheet using a punch having a curved head and being operatively associated with the bender assembly, the pressure being applied by moving the punch against the metal sheet using a damped punch driver operatively associated with the bender assembly.

Preferably, the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member having a working surface and defining a receiving cavity adjacent the working surface.

Preferentially, the step of holding the metal sheet against translational movement includes holding the metal sheet using a bender assembly having a plate that engages and applies pressure to the metal sheet prior to the arrival of the punch, and holds the metal sheet stationary during punch application.

It is preferred that the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate supporting the punch in a downwardly directed manner for selective engagement with the metal sheet.

It is further preferred that the step of moving the punch using a damped punch driver includes moving the punch using a punch driver damped with a plurality of springs operatively associated with the bender assembly. Preferably, the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs extending intermediate a spring support plate and punch plate supporting the curved punch in a downwardly directed manner for selective engagement with the metal sheet. Preferentially, the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate in a predetermined pattern for balanced force application. It is preferred that the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate with each of the plurality of springs having a spring stabilizer operatively associated therewith to keep each of the plurality of springs in place intermediate the spring support plate and the punch plate.

Preferably, the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member mounted to a base plate, having a working surface and defining a receiving cavity adjacent the working surface. It is preferred that the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate fixed to the bender assembly in alignment with the base plate to support the punch in a downwardly directed manner toward the receiving cup for selective engagement with the metal sheet at the work surface and receiving cavity. It is further preferred that the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs mounted to a spring support plate fixed to the bender assembly in alignment with the base plate, the spring support plate having a hole defined therein in alignment with the punch for passage of the punch therethrough in a downwardly directed manner for selective engagement with the metal sheet at the work surface and receiving cavity.

Preferentially, the step of applying pressure includes applying pressure to the bender assembly in a machine press.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a home appliance according to the preferred embodiment of the present invention;

FIG. 2 is a perspective view of the home appliance illustrated in FIG. 1;

FIG. 3 is a perspective view of a portion of a front panel of the home appliance illustrated in FIG. 2;

FIG. 4 is an underside view of the panel illustrated in FIG. 3;

FIG. 5 is a front view of a bender assembly according to the preferred embodiment of the present invention;

FIG. 6 is a rear view of the bender assembly illustrated in FIG. 5;

FIG. 7 is a perspective view of the receiver plate of the bender assembly illustrated in FIG. 5;

FIG. 8 is an underside view of the spring plate of the bender assembly illustrated in FIG. 5;

FIG. 9 is a top view of the punch plate separated from the spring plate of the bender assembly illustrated in FIG. 5;

FIG. 10 is a perspective view of a metal plate being fabricated into a panel using the bender assembly of FIG. 5;

FIG. 11 is a perspective view of pressure being applied to the bender assembly of FIG. 5 by a machine press;

FIG. 12 is a perspective view of the bender assembly pressing a curved portion into the panel illustrated in FIG. 11;

FIG. 13 is a perspective view of the machine press relieving pressure on the bender assembly as illustrated in FIG. 12; and

FIG. 14 is a perspective view of the finished panel emerging from being fabricated by the bender assembly device illustrated in FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to the drawings and, more particularly, to FIGS. 1 and 2, a range is illustrated generally at 10 and includes a floor-standing, box-like body 12 that defines a number of operational openings including an oven 18 as seen in FIG. 1 and a steamer unit which may be combined with a convection oven as seen at 24 in FIG. 2. A control panel 22 is located above the oven 18 and steamer 24. A first door 20 covers the oven 18 and a second door 26 covers the steamer 24.

A front panel 14 overlies the internal portions of the range 10 and is generally covered by the doors 20, 26 in the closed position. Curved panel portions are defined over the face of the front panel 14, and, for example, are defined at the corners of the oven 18 as illustrated at 16 in FIG. 1, and at the corners of the steamer/oven combination 24, as illustrated at 28 in FIG. 2. According to the present invention such corners are smooth and free of metal distortion resulting from fabrication of the front panel 14.

As seen in FIGS. 3 and 4, a portion of a front panel 14 is illustrated on either side showing a portion having a corner formed therein. It should be noted that lines on the illustrations, especially FIG. 3, are meant to indicate curvature and are not to be construed as metal distortion. There, a corner 16 includes a curved corner surface 30 and an in-turned flange 32 extending substantially perpendicularly away from the curved corner surface 30 with the curved corner surface 30 and the flange 32 defining a smoothly curved junction. The flange 32 is seen in FIG. 4 as extending away from the underside 38 of the panel 14 at the underside curved corner surface 40.

An opening 34 is formed at the innermost portion of the corner 30 and extends from the flat curved portion 30 onto the flange 32 for relief of internal pressure during bending and to enhance the ability of the panel 14 to emerge from bending with a smooth, substantially undistorted finish. Additionally, spaces 36 are defined in the panel 14 as keyhole-shaped openings at either end of the flange 32 to further enhance the ability of the panel 14 to resist wrinkling and distortion during bending.

With reference to FIG. 5, a bender assembly 42 is illustrated at an operational position in a machine press, or press brake including a upper ram P₁ and a lower die support P₂. In operation, the press brake will drive the ram P₁ toward the die support P₂, with the resulting pressure acting on any material therebetween.

The bender assembly 42 includes three generally planar plates that can be made from solid aluminum billet, including a punch plate 44 for contact with the ram P₁ and a die plate 48 for support by the die support P₂. A spring plate 46 is intermediate the punch plate 44 and the die plate 48.

The punch plate 44 includes a generally cylindrical punch 50 extending downwardly and away from the punch plate 44 at approximately the center of the punch plate 44. The spring plate 46 includes nine springs 60 generally evenly spaced throughout the spring support plate 46 which are maintained in position by spring stabilizers 62 that extend through the coil springs 60 and are rods firmly mounted to the spring plate 46 within the coil of each spring 60. The spring supports 62 are accommodated by the punch plate 44 using openings that allow the spring supports 62 to pass therethrough, so as the punch plate 44 descends toward the spring plate 46, the springs 60 are compressed and the spring supports 62 project upwardly from the punch plate 44, as seen in FIG. 12.

As seen in FIG. 5, the die plate 48 includes a die 64 having a receiving well 68 with the die 64 being configured to support the metal sheet and to cooperate with the punch 50 to perform the shaping of the metal sheet during bending operations.

With reference to FIG. 6, the plates 44, 46 and 48 are mounted between two vertically extending stanchions 56, 58. With continued reference to FIG. 5 and FIG. 6, it can be seen that nine coil springs are mounted intermediate the punch plate 44 and the spring plate 46. As seen in FIG. 6 and FIG. 9, the nine springs include three springs equally spaced along the rear portion of the spring plate 44 and two springs at each front corner of the spring plate 44 forming an outer spring group 76. Four springs are evenly spaced around the punch and placed inwardly of the other five springs, forming an inner spring group 74. Such even spacing of the springs 60 provides an even damping force resisting the downwardly pressing ram to ease internal stresses on any metal being bent in the present bender assembly 42. The spring plate 46 also engages the panel 14 before the punch 50 contacts the panel 14, and uses the force of the ram P₁ via the springs 60 to hold the panel 14 in position for bending. The spacing of the springs within the inner spring group 74 and the outer spring group 76 results in even, firm holding pressure in the region of the bend. The more rigidly the panel 14 is held, the less likely metal distortions will result from bending.

Turning now to FIG. 7, the die 64 includes a generally curved wall defining a working surface 66 and a receiving cup 68, open on one side and located adjacent the working surface 66, with the receiving cup 68 having approximately the radius of the punch 50. A working trough 70 is defined by the die 64 adjacent the working surface 66 and the receiving cup 68. The die 64 is mounted to the die support plate 48 using fasteners 72. The working surface 66 supports the sheet metal blank used to form the panel 14, a portion of which is driven into the receiving cup 68 by the punch 60.

Turning to FIG. 8, the underside of the spring plate 46 is shown as defining an opening 54 through which the punch 50 must pass to reach a workpiece, such as the panel 14, at the die 64. The punch 50 has a curved or sloped head 52 which helps to define the curvature and the rate of bending at the corner when forming the panel 14 from the metal blank. Gradual bending contributes to the resultant smooth and undistorted panel 14. Such curvature can be seen in FIG. 9 which illustrates the spring plate 46 raised from the punch plate 44 which is shown inverted. The location of the punch opening 54 in the spring plate 46 is also shown in FIG. 9.

In operation, and with reference to FIG. 10, a sheet blank forming a panel 14 is placed intermediate the die 64 and the lower surface of the spring plate 46, the ram P₁ being raised to accommodate such positioning of the work piece. The bender assembly 42 is mounted to the machine press or press brake with the die plate 48 is supported on the die support P₂.

With reference to FIG. 11, the ram P₁ is driven downwardly to press the work piece supported on the die 64. The spring plate 46 engages the panel 14 and holds the panel 14 rigidly in position for bending. The springs 60 act to absorb or dampen any irregularity or jerkiness of ram motion by providing a cushion against the force of the ram, as well as distributing the ram force evenly across the panel 14 adjacent the proposed bend. Further, the springs 60 assist the spring plate 46 in holding the panel 14 against any possible translational movement.

As seen in FIG. 12, the pressing process has bottomed out, with the punch plate 44 and spring plate 46 at their closest positions with the springs 60 fully compressed, and the spring supports 62 projecting a maximum distance beyond the punch plate 44. The punch 50 has passed through the opening 54 in the spring plate 46, and has driven the metal of the panel 46 gradually downwardly into the receiving well 68 of the die 64. The rigidly held panel 14 is not pulled into the receiving well 68 and accordingly further avoids metal distortion during the bend.

As seen in FIG. 13, the ram P₁ has reversed motion and is releasing the pressure on the punch plate 44, thereby allowing the springs 60 to assist the movement of the ram P1 in driving the punch plate 44 away from the die 64.

As seen in FIG. 14, the spring plate 46 and the punch plate 44 have been lifted from any further action on the die 64 allowing the panel 14 to emerge from the die 64 having a smooth undistorted corner 28.

By the above, the present invention provides a home appliance with a front panel that is substantially smooth and substantially distortion free. By operation of the spring plate 46 to hold the panel 14 rigidly in place, to distribute the ram force evenly over the panel 14 and to damp the ram force, in combination with gradual curving provided by the smoothly curved punch 50, a smooth and undistorted curved panel 14 is achieved.

It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of a broad utility and application. While the present invention is described in all currently foreseeable embodiments, there may be other, unforeseeable embodiments and adaptations of the present invention, as well as variations, modifications and equivalent arrangements, that do not depart from the substance or scope of the present invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. 

What is claimed is:
 1. A home appliance comprising: an appliance body having an internal framework; and a metal panel covering a portion of the internal framework, the panel having a curved portion turned inwardly toward an interior of the appliance, wherein the panel surface is substantially smooth and substantially undistorted, the panel being fabricated by engaging a metal sheet with a bender assembly, holding the metal sheet against translational movement using the bender assembly and applying pressure to the metal sheet using a punch having a curved head and being operatively associated with the bender assembly, the pressure being applied by moving the punch against the metal sheet using a damped punch driver operatively associated with the bender assembly.
 2. The home appliance of claim 1 wherein the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member having a working surface and defining a receiving cavity adjacent the working surface.
 3. The home appliance of claim 1 wherein the step of holding the metal sheet against translational movement includes holding the metal sheet using a bender assembly having a plate that engages and applies pressure to the metal sheet prior to the arrival of the punch, and holds the metal sheet stationary during punch application.
 4. The home appliance of claim 1 wherein the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate supporting the punch in a downwardly directed manner for selective engagement with the metal sheet.
 5. The home appliance of claim 1 wherein the step of moving the punch using a damped punch driver includes moving the punch using a punch driver damped with a plurality of springs operatively associated with the bender assembly.
 6. The home appliance of claim 5 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs extending intermediate a spring support plate and a punch plate supporting the curved punch in a downwardly directed manner for selective engagement with the metal sheet.
 7. The home appliance of claim 6 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate in a predetermined pattern for balanced force application.
 8. The home appliance of claim 7 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate with each of the plurality of springs having a spring stabilizer operatively associated therewith to keep each of the plurality of springs in place intermediate the spring support plate and the punch plate.
 9. The home appliance of claim 1 wherein the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member mounted to a base plate, having a working surface and defining a receiving cavity adjacent the working surface.
 10. The home appliance of claim 9 wherein the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate fixed to the bender assembly in alignment with the base plate to support the punch in a downwardly directed manner toward the receiving cup for selective engagement with the metal sheet at the work surface and receiving cavity.
 11. The home appliance of claim 10 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs mounted to a spring support plate fixed to the bender assembly in alignment with the base plate, the spring support plate having a hole defined therein in alignment with the punch for passage of the punch therethrough in a downwardly directed manner for selective engagement with the metal sheet at the work surface and receiving cavity.
 12. The home appliance of claim 1 wherein the step of applying pressure includes applying pressure to the bender assembly in a machine press.
 13. A range comprising: a range body having an internal framework; a metal panel covering a portion of the internal framework, the panel having a curved portion turned through the curve inwardly toward an interior of the range, wherein the panel surface adjacent the curve is substantially smooth and substantially undistorted, the panel being fabricated by engaging a metal sheet with a bender assembly, holding the metal sheet against translational movement and applying pressure to the metal sheet using a punch having a curved head and being operatively associated with the bender assembly, the pressure being applied by moving the punch against the metal sheet using a damped punch driver operatively associated with the bender assembly.
 14. The range of claim 13 wherein the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member having a working surface and defining a receiving cavity adjacent the working surface.
 15. The range of claim 13 wherein the step of holding the metal sheet against translational movement includes holding the metal sheet using a bender assembly having a plate that engages and applies pressure to the metal sheet prior to the arrival of the punch, and holds the metal sheet stationary during punch application.
 16. The range of claim 13 wherein the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate supporting the punch in a downwardly directed manner for selective engagement with the metal sheet.
 17. The range of claim 13 wherein the step of moving the punch using a damped punch driver includes moving the punch using a punch driver damped with a plurality of springs operatively associated with the bender assembly.
 18. The range of claim 13 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs extending intermediate a spring support plate and a punch plate supporting the curved punch in a downwardly directed manner for selective engagement with the metal sheet.
 19. The range of claim 18 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate in a predetermined pattern for balanced force application.
 20. The range of claim 19 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs arranged on the spring support plate with each of the plurality of springs having a spring stabilizer operatively associated therewith to keep each of the plurality of springs in place intermediate the spring support plate and the punch plate.
 21. The range of claim 13 wherein the step of engaging includes engaging a metal sheet with a bender assembly having a receiving cup including an upstanding wall member mounted to a base plate, having a working surface and defining a receiving cavity adjacent the working surface.
 22. The range of claim 21 wherein the step of applying pressure using a punch operatively associated with a bender assembly includes using a bender assembly having a punch plate fixed to the bender assembly in alignment with the base plate to support the punch in a downwardly directed manner toward the receiving cup for selective engagement with the metal sheet at the work surface and receiving cavity.
 23. The range of claim 22 wherein the step of moving the punch includes moving the punch using a damped punch driver includes using a punch driver damped with a plurality of springs mounted to a spring support plate fixed to the bender assembly in alignment with the base plate, the spring support plate having a hole defined therein in alignment with the punch for passage of the punch therethrough in a downwardly directed manner for selective engagement with the metal sheet at the work surface and receiving cavity.
 24. The home appliance of claim 13 wherein the step of applying pressure includes applying pressure to the bender assembly in a machine press. 